28865807 has 4 divisors (see below), whose sum is σ = 30385080. Its totient is φ = 27346536.

The previous prime is 28865803. The next prime is 28865821. The reversal of 28865807 is 70856882.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28865807 - 2² = 28865803 is a prime.

It is a super-2 number, since 2×28865807² = 1666469627522498, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28865801) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 759608 + ... + 759645.

It is an arithmetic number, because the mean of its divisors is an integer number (7596270).

Almost surely, 2^28865807 is an apocalyptic number.

28865807 is a deficient number, since it is larger than the sum of its proper divisors (1519273).

28865807 is a wasteful number, since it uses less digits than its factorization.

28865807 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1519272.

The product of its (nonzero) digits is 215040, while the sum is 44.

The square root of 28865807 is about 5372.6908528223. The cubic root of 28865807 is about 306.7570607554.

The spelling of 28865807 in words is "twenty-eight million, eight hundred sixty-five thousand, eight hundred seven".